Two of Saddam Hussein's key aides have been hanged in Baghdad, two weeks after the chaotic execution of the former Iraqi president.
Barzan al-Tikriti headed Saddam Hussein's secret police
There were "no violations" this time, officials said, but Saddam Hussein's half-brother, Barzan al-Tikriti, was decapitated as he was hanged.
He and Awad Hamad al-Bandar, a top judge under Saddam, were convicted over the killing of 148 Shias in the 1980s.
The country's president Jalal Talabani had urged their executions be delayed.
Government officials said the decapitation of Barzan was not abnormal, although it was rare for the head to be severed during hanging. One described it as "an act of God".
One of those present, public prosecutor Jaafar al-Moussawi, told the BBC that when the trap door opened, he could only see the rope dangling.
Execution intended to break the neck, not strangle
'Long drop' method developed in late 19th century
Length of rope calculated using prisoner's weight
Drop is usually 4ft-10ft (1.3m-3m)
Too long a drop leads to decapitation
"I thought the convict Barzan Ibrahim al-Tikriti had escaped the noose. I shouted that he's escaped the noose, go down and look for him. I went down a few steps ahead of the others to see: I found out that his head had separated from his body."
The executions took place at 0300 (0000 GMT), apparently in the same building where Saddam Hussein was put to death on 30 December after being convicted of the same crime.
The manner of his execution has sparked controversy around the world, after unofficial mobile phone footage was released showing him being taunted and insulted in his final moments.
Iraq's Shia-dominated government pledged a full investigation. Government spokesman Ali al-Dabbagh said this time everyone present at the facility had signed a document pledging appropriate behaviour.
Correspondents say the gruesome detail about Barzan's decapitation was probably made public in order to avoid it being leaked later with accompanying allegations of mistreatment.
A member of their defence team, Issam al-Ghazzawi, told the Reuters news agency he was outraged by the execution.
"When a man is hanged, he does not lose his head," he said. "The way Barzan was executed is shameful."
The bodies of the men are to be handed over to their families within the next few days.
Barzan Ibrahim al-Tikriti was the former Iraqi leader's half-brother and served as the head of his feared secret police, the Mukhabarat.
He was a senior figure in the Iraqi government at the time of the US-led invasion of 2003 and was a key target for capture.
During his captivity, it emerged he had cancer and a number of calls were made for his release for treatment on humanitarian grounds.
Awad Hamad al-Bandar was chief justice of the Iraqi Revolutionary Court. According to his indictment, he conducted show trials which often led to summary death sentences.
The court he headed issued death sentences against residents of the town of Dujail in the aftermath of the failed assassination attempt on the president on 8 July 1982.
His lawyers argued that he had simply been following the letter of Iraqi law, as it was written at the time, and also denied that he had ordered the execution of juveniles.